Sounds like an interesting project. What is the camera for?You can find motors & power supplies here www.mpja.comYou will need some relays or MOSFETs to control power going to the motors.Instead of a tact switch, a microswitch, the kind that has an arm on it, may be easier to mount and adjust.

I kind of have this figured out. I need to run a wire from the 5v rail to an analog input pin on the arduino. Then I need to have a wire from another analog pin to a MOSFET gate pin. Connect the + terminal of the 12v power supply to the MOSFET source pin. The connect a cable to the drain pin of the MOSFET to the motor. Then wire the - terminals together. Now the only thing left is the sketch. Where should I start?

Your last post addresses a motor driver.This is the circuit you want for that, using an N channel logic level MOSFET. The MOSFET will turn the motor on when the arduino pin it is connected to is high (can be any of the pins, with digitalWrite (pinX, HIGH); to turn it on & digitalWrite(pinX, LOW); to turn it off.The second diagram shows typical ways of connecting switches & LEDs to receive inputs & have user indicators.There are plenty of tutorials available that show the bacics of a sketch, do a little reading & try one, then post again with questions.